Maternal and foetal outcomes in pregnant systemic lupus erythematosus patients: an incident cohort from a stable referral population followed during 1990-2010

Objectives: To assess the impact of systemic lupus erythematosus (SLE) on pregnancy outcome in a cohort of incident pregnant lupus patients referred to a Danish university hospital during 1990-2010. Method: All pregnant lupus patients were referred to the university hospital from a stable referral area with approximately 1.4 million inhabitants. Eighty-four pregnancies in 39 women were registered using the Danish National Registry and retrospective reviewing of medical records, laboratory results, and midwifery records from the Department of Rheumatology, the Department of Obstetrics and Gynaecology, and possible other departments. Data were compared to 29 059 births during 2005-2010, covering all births from the referral area. Results: The 84 SLE pregnancies resulted in 62 live births. SLE flares developed in 46.4%, pre-eclampsia in 8.3%, and HELLP syndrome in 4.8% of cases. Significantly higher rates of premature delivery (p = 0.0032), caesarean section (p = 0.015), hypertension (p = 0.025), and intrauterine growth retardation (IUGR) (p = 0.003) were found. Disease activity significantly (p = 0.021) increased the risk of prematurity threefold. Antiphospholipid antibody (aPL) presence significantly (p = 0.002) increased the risk of spontaneous abortion threefold. Two babies died after extreme preterm birth. Two had neonatal lupus syndrome (NLS) and one had congenital heart block (CHB). Birth weight and length were significantly lower in the SLE cohort. An unexpectedly high number of cardiac septum defects (9.7%) were observed. Conclusions: From a stable referral area, an incident cohort of SLE pregnancies were mostly successful, but maternal and foetal complications were observed in one-half and one-third of cases, respectively. Outcome risk factors were identified. A possible new observation is a high frequency of cardiac septum defects.